[vta/trunk?] simplify lib changes detection with bootstrap4-debug

[Alexandre Oliva <aoliva at redhat dot com>]

This uglyish hack short-circuits the build of host tools for stageb4g
(bootstrap4-debug), using the tools built in stageb3g2, and then
modifies the specs file of stageb4g-gcc so as to disable or modify the
debug-info (or other) options passed from the compiler driver to the
compiler proper.  The intended use case is:

.../configure ...; make bootstrap-debug; \
make prepare-bootstrap4-debug-lib-$which; \
make bootstrap4-debug; \
rm compare3-debug; make compare3-debug

where $which can be replaced with:

* g0, to build the bootstrap4-debug libraries with -g0;

* novta, to build them with -fno-var-tracking-assignments.  ATM this
  makes sense only in the vta branch, where the option exists and its
  opposite is the default;  Or

* custom, to build them after an arbitrary transformation in the spec
  file, specified through a Makefile macro set to a sed script.  Maybe
  I could do away with this and then we could just use
  prepare-bootstrap-debug-lib, and then tweak the specs file by hand?

Thoughts?  Is this useful for the trunk, without the vta-specific
bits, along with the two other top-level compare and bootstrap-debug
patches I've just posted?

for  ChangeLog.vta
from  Alexandre Oliva  <aoliva@redhat.com>

	* Makefile.tpl (bootstrap4-debug-init): New macro.
	(bootstrap4-debug-lib-gcc-clean): New macro.
	(cp-lR): New macro.
	(prepare-bootstrap4-debug-lib): New target.
	(clean-bootstrap4-debug-lib): New target.
	(sed-script-prepare-bootstrap4-debug-lib-g0): New macro.
	(sed-script-prepare-bootstrap4-debug-lib-novta): New macro.
	(sed-script-prepare-bootstrap4-debug-lib-custom): New macro.
	(prepare-bootstrap4-debug-lib-g0): New target.
	(prepare-bootstrap4-debug-lib-novta): New target.
	(prepare-bootstrap4-debug-lib-custom): New target.
	* Makefile.in: Rebuilt.
	
Index: Makefile.tpl
===================================================================
--- Makefile.tpl.orig	2007-11-03 04:44:12.000000000 -0200
+++ Makefile.tpl	2007-11-05 04:19:36.000000000 -0200
@@ -1609,6 +1609,53 @@ configure-gdb: $(CONFIGURE_GDB_TK)
 all-gdb: $(gdbnlmrequirements) $(GDB_TK)
 install-gdb: $(INSTALL_GDB_TK)
 
+@if gcc-bootstrap
+bootstrap4-debug-init = stgsrc=stageb3g2 stgdst=stageb4g
+bootstrap4-debug-lib-gcc-clean = stamp-gnatlib* stamp-tools ada/rts
+
+cp-lR = cp -lR
+
+.PHONY: prepare-bootstrap4-debug-lib
+prepare-bootstrap4-debug-lib:
+	@r=`${PWD_COMMAND}`; export r; \
+	s=`cd $(srcdir); ${PWD_COMMAND}`; export s; \
+	: $(MAKE); $(stage); \
+	$(bootstrap4-debug-init) didgcc=false; \
+	for d3 in $$stgsrc-*; do \
+	  case $$d3 in "$$stgsrc-$(TARGET_SUBDIR)") continue ;; esac; \
+	  d4=`echo $$d3 | sed s,^$$stgsrc,$$stgdst,`; \
+	  if test -d $$d4; then \
+	    echo $$d4 already set up, skipping...; \
+	    continue; \
+	  fi; \
+	  d4t=$$d4.tmp; \
+	  rm -rf $$d4t || :; \
+	  $(cp-lR) $$d3/. $$d4t; \
+	  case $$d3 in "$$stgsrc-gcc") \
+	    (cd $$d4t && rm -rf $(bootstrap4-debug-lib-gcc-clean)) || :;; \
+	  esac; \
+	  mv $$d4t $$d4; \
+	done
+
+.PHONY: clean-bootstrap4-debug-lib
+clean-bootstrap4-debug-lib: prepare-bootstrap4-debug-lib
+	@$(bootstrap4-debug-init); \
+	rm -rf $$stgdst-$(TARGET_SUBDIR) || :; \
+	(cd $$stgdst-gcc && rm -rf $(bootstrap4-debug-lib-gcc-clean)) || :
+
+sed-script-prepare-bootstrap4-debug-lib-g0 = 's,%{g\*},,'
+sed-script-prepare-bootstrap4-debug-lib-novta = 's,%{g\*},& %{!fvar-tracking-assignments:%{!fno-var-tracking-assignments:-fno-var-tracking-assignments}},'
+sed-script-prepare-bootstrap4-debug-lib-custom = 's,x,x,'
+
+.PHONY: prepare-bootstrap4-debug-lib-g0 prepare-bootstrap4-debug-lib-novta prepare-bootstrap4-debug-lib-custom
+prepare-bootstrap4-debug-lib-g0 prepare-bootstrap4-debug-lib-novta \
+prepare-bootstrap4-debug-lib-custom: prepare-bootstrap4-debug-lib
+	@$(bootstrap4-debug-init); \
+	rm -f $$stgdst-gcc/specs; \
+	sed $(sed-script-$@) < $$stgsrc-gcc/specs > $$stgdst-gcc/specs
+
+@endif gcc-bootstrap
+
 # Serialization dependencies.  Host configures don't work well in parallel to
 # each other, due to contention over config.cache.  Target configures and 
 # build configures are similar.
Index: Makefile.in
===================================================================
--- Makefile.in.orig	2007-11-03 04:44:12.000000000 -0200
+++ Makefile.in	2007-11-05 04:19:50.000000000 -0200
@@ -53247,6 +53247,53 @@ configure-gdb: $(CONFIGURE_GDB_TK)
 all-gdb: $(gdbnlmrequirements) $(GDB_TK)
 install-gdb: $(INSTALL_GDB_TK)
 
+@if gcc-bootstrap
+bootstrap4-debug-init = stgsrc=stageb3g2 stgdst=stageb4g
+bootstrap4-debug-lib-gcc-clean = stamp-gnatlib* stamp-tools ada/rts
+
+cp-lR = cp -lR
+
+.PHONY: prepare-bootstrap4-debug-lib
+prepare-bootstrap4-debug-lib:
+	@r=`${PWD_COMMAND}`; export r; \
+	s=`cd $(srcdir); ${PWD_COMMAND}`; export s; \
+	: $(MAKE); $(stage); \
+	$(bootstrap4-debug-init) didgcc=false; \
+	for d3 in $$stgsrc-*; do \
+	  case $$d3 in "$$stgsrc-$(TARGET_SUBDIR)") continue ;; esac; \
+	  d4=`echo $$d3 | sed s,^$$stgsrc,$$stgdst,`; \
+	  if test -d $$d4; then \
+	    echo $$d4 already set up, skipping...; \
+	    continue; \
+	  fi; \
+	  d4t=$$d4.tmp; \
+	  rm -rf $$d4t || :; \
+	  $(cp-lR) $$d3/. $$d4t; \
+	  case $$d3 in "$$stgsrc-gcc") \
+	    (cd $$d4t && rm -rf $(bootstrap4-debug-lib-gcc-clean)) || :;; \
+	  esac; \
+	  mv $$d4t $$d4; \
+	done
+
+.PHONY: clean-bootstrap4-debug-lib
+clean-bootstrap4-debug-lib: prepare-bootstrap4-debug-lib
+	@$(bootstrap4-debug-init); \
+	rm -rf $$stgdst-$(TARGET_SUBDIR) || :; \
+	(cd $$stgdst-gcc && rm -rf $(bootstrap4-debug-lib-gcc-clean)) || :
+
+sed-script-prepare-bootstrap4-debug-lib-g0 = 's,%{g\*},,'
+sed-script-prepare-bootstrap4-debug-lib-novta = 's,%{g\*},& %{!fvar-tracking-assignments:%{!fno-var-tracking-assignments:-fno-var-tracking-assignments}},'
+sed-script-prepare-bootstrap4-debug-lib-custom = 's,x,x,'
+
+.PHONY: prepare-bootstrap4-debug-lib-g0 prepare-bootstrap4-debug-lib-novta prepare-bootstrap4-debug-lib-custom
+prepare-bootstrap4-debug-lib-g0 prepare-bootstrap4-debug-lib-novta \
+prepare-bootstrap4-debug-lib-custom: prepare-bootstrap4-debug-lib
+	@$(bootstrap4-debug-init); \
+	rm -f $$stgdst-gcc/specs; \
+	sed $(sed-script-$@) < $$stgsrc-gcc/specs > $$stgdst-gcc/specs
+
+@endif gcc-bootstrap
+
 # Serialization dependencies.  Host configures don't work well in parallel to
 # each other, due to contention over config.cache.  Target configures and 
 # build configures are similar.

-- 
Alexandre Oliva         http://www.lsd.ic.unicamp.br/~oliva/
FSF Latin America Board Member         http://www.fsfla.org/
Red Hat Compiler Engineer   aoliva@{redhat.com, gcc.gnu.org}
Free Software Evangelist  oliva@{lsd.ic.unicamp.br, gnu.org}